The instant invention relates to a cartridge case having a metal base and a sleeve casing made from a synthetic plastic material connected to the metal base by a snap lock, wherein a tubular section extends from the base piece into the combustion chamber of the cartridge case along the inside surface of the sleeve casing.
In a known cartridge case of this type (AU-PS 164 502), the tubular section extending along the sleeve casing is made as one piece with the base, and is therefore also made of metal and is of comparatively minimal thickness. If high gas pressures, e.g., 4000 to 5000 bar, are produced when the propellant charge in the combustion chamber is detonated, a plastic, i.e., a permanent, deformation of the thin-walled tubular section occurs, especially since the sleeve casing is made from a synthetic plastic material which does not afford any appreciable reinforcement. Such a plastic deformation in the metal piece, however, creates the danger that the cartridge case will jam in the cartridge chamber after firing and can then be removed only with difficulty, generally requiring specialized tools.
A cartridge case (AT-PS 350 942) consisting of an outer sleeve casing made from a plastic material, a base piece, also preferably made from a plastic material, located therein, and an intermediate part firmly connecting the base piece to the sleeve into one unit is also known. The intermediate part surrounds the two front ends of the base piece and can therefore be made only by an injection molding process from an injection molding material. This cartridge case also is suitable only for comparatively low gas pressures, the special design being intended to make it possible to re-use the cartridge case.
Compared to this, it is the object of the instant invention to improve the cartridge case described initially by simple means so that it is able to withstand high gas pressures while reducing any possibilities of jamming.